What do the following two equations represent? $4x-2y = 4$ $4x+8y = -1$
Explanation: Putting the first equation in $y = mx + b$ form gives: $4x-2y = 4$ $-2y = -4x+4$ $y = 2x - 2$ Putting the second equation in $y = mx + b$ form gives: $4x+8y = -1$ $8y = -4x-1$ $y = -\dfrac{1}{2}x - \dfrac{1}{8}$ The slopes are negative inverses of each other, so the lines are perpendicular.